Wound drain catheters generally have a flexible drain portion and a flexible outflow tube portion. The drain portion is integral or attached to the outflow portion. The drain portion is placed in or adjacent the wound site and the outflow portion will pass through the skin of the patient and be connected to a source of vacuum to drain the wound site.
Trocars are commonly used to insert wound drainage catheters or tubing into a drainage site adjacent a surgical wound or from a surgical wound site through the skin of a patient. These trocars usually have the catheter or tubing attached to the one end of the trocar so that the tubing follows the trocar along a path through the patient's body.
Several techniques may be used to insert a wound drain catheter in the patient's body. For example, a surgeon may simply place the drain portion and a small part of the outflow tube portion in the wound, close the incision, and suture around the outflow tube Portion. This technique is somewhat unsatisfactory, since it is difficult to completely seal the area around the outflow tube by suturing, and thus, the wound may become infected. A more satisfactory technique is to pass a trocar, preattached to the end of the outflow tube, through healthy tissue by entering the patient's body at a point within the wound and exiting at a point adjacent to the wound. The surgeon pulls the outflow tube portion through the tissue with the trocar until the catheter is properly positioned, with the drain in the wound. Since the outflow tube exits the body at a point adjacent the wound, the wound can be completely closed by suturing, thereby reducing the risk of infection.
The trocars are manufactured with a slight bend near the pointed end to allow them to be manipulated through the skin of the patient. The catheter or drainage tubing will follow the path made by the trocar until the drainage end of the tubing is in its desired position within the body and the outflow portion of the catheter outside the patient's body. At that time the trocar will then be cut from the tubing and the tubing connected to a wound drain evacuator or a source of vacuum.
U.S Pat. No. 4,398,910 discloses the use of trocar in the manner described above.
U.S. Pat. No. 4,359,053 discloses the fastening of plastic tubing to a trocar or needle for the same purpose.
The trocars are usually made of very hard surgical grade stainless steel or other materials so that they may be sharpened to a very fine point to allow the distal end or sharpened end of the trocar to pass through the body tissue. There is generally a slight bend, about 15.degree., in the trocar when manufactured as shown in U.S. Pat. No. 4,398,910 to allow the trocar to be manipulated through the body of the patient to correctly position the wound drainage tubing in the position desired by the surgeon. In many instances, it is difficult to properly position the wound drainage tubing because it is difficult to pass the trocar through the patient's body without hitting a solid structure such as bone.